On a weekly basis, more college women than men exceed the drinking recommendations from the National Institutes of Health, according to a Harvard study conducted at three New England universities.

The study found that 64 percent of women in college exceed weekly guidelines for alcohol consumption.

The National Institute on Alcohol Abuse and Alcoholism (NIAAA) recommends that, on average, women drink no more than three drinks per day or seven drinks per week in order to keep a clean bill of health. The "beverage ceiling" for men is less stringent and is set at four drinks per day and 14 drinks per week.

"Recommended drinking limits are lower for women than for men because research to date has found that women experience alcohol-related problems at lower levels of alcohol consumption than men," explained co-author Bettina B. Hoeppner, a psychologist at Harvard Medical School and the Massachusetts General Hospital Center for Addiction Medicine

It was unclear, however, if men and women differ in their adherence to the NIAAA's drinking guideines.

The drinking habits of 992 college first-years were tracked over the course of three consecutive school years. Every two weeks, the volunteer participants received an e-mail that linked them to an online survey where they kept a tally of their alcohol consumption.

They researchers found that female college drinkers were more likely to exceed the weekly limit than college men. A similar number of girls and guys - about one in four - went over the daily maximum on a regular basis.

"It is always important to take gender into account when studying health or risk behaviors," added Melissa A. Lewis, a psychiatrist and behavioral sciences at the University of Washington who wasn't involved in the study. "Men have more of an enzyme in the stomach that lowers the amount of alcohol that makes it into the bloodstream. Also, women have less blood going through the bloodstream than a man at the same weight, so alcohol gets more concentrated in the bloodstream."

Drinking is almost considered an unofficial rite of passage in college. This study found that three out of four college students had at least one drink during their freshman year. In contrast, the three out of four U.S. adults either abstain from alcohol entirely or drink within low-risk limits, according to a 2009 NIAAA study.

Breaking the weekly recommendations from the NIAAA is linked to a higher risk of long-term health conditions, like liver disease, heart disease, and sleep disorders. Exceeding the daily limits can trigger substantial cognitive impairment and is connected to higher likelihood of self-injury, violent crime like sexual assault, and alcohol-related car accidents.

"By exceeding weekly limits more often than men, women are putting themselves at increased risk for experiencing such long-term effects," said Hoeppner.

Male undergrads also drank less over time, while the level of imbibing among first-year women remained steady

"Current preventative interventions often do not focus on weekly drinking recommendations," said Lewis, but rather they focus on binge drinking. "These findings highlight the need for prevention efforts to focus on both daily and weekly limits to reduce harm from short- and long-term negative consequences."

The other co-authors of the study were Anna L. Paskausky, of the Center for Addiction Medicine of Harvard Medical School and the Connell School of Nursing at Boston College, and Kristina M. Jackson and Nancy P. Barnett of the Center for Alcohol and Addiction Studies at Brown University.

Source: Hoeppner BB, et al. Sex Differences in College Student Adherence to NIAAA Drinking Guidelines. Alcoholism: Clinical & Experimental Research. 2013